APPEARANCE: Atuikakura is an enormous sea cucumber which lives deep in Uchiura Bay in Hokkaido.

BEHAVIOR: Atuikakura is rarely seen due its underwater lifestyle. It spends most of its time deep in the water, occasionally attaching itself to chunks of driftwood and floating to other parts of the bay.

INTERACTIONS: Despite rarely being seen, Atuikakura can be very dangerous to ships on the bay. When Atuikakura gets startled, it thrashes about wildly, smashing or capsizing ships which happen to be bear it. It also sometimes mistakes a wooden boat for a piece of driftwood, attaches its mouth to it, and drags the ship under the waves.

ORIGIN: Atuikakura is the Japanese transcription of its Ainu name, atuy kakura. Atuy is the Ainu word for the sea, and kakura means sea cucumber. According to local legend, Atuikakura was formed when a mouru—the traditional undergarment of Ainu women—washed down a river and into the bay. The mouru settled at the bottom of Uchiura Bay and and turned into a giant sea cucumber.